In the current state of operations, occasions arise such that threats (or targets) must be detected at a standoff distance. Some threats contain components whose permittivity contrasts substantially with that of the emplacement; such is the case with many threats that are buried. The reception of a subsurface linear radar response from an area whose surface is otherwise undisturbed indicates the presence of a threat. Others threats contain metal contacts and semiconductor junctions whose nonlinear electromagnetic response contrasts with that of the emplacement; such is the case with radio frequency (RF) electronics. The reception of a nonlinear radar response from an area that does not otherwise contain electronics indicates the presence of another class of threat. Often, threats contain dielectric, as well as electronic components, hence they will respond to both linear and nonlinear excitation and either linear or nonlinear radar with detect such as threat. Hence, there exists a need to detect both types of threats, whether or not they are collocated using a single assembly or unit.